29138640 has 80 divisors (see below), whose sum is σ = 90851328. Its totient is φ = 7725568.

The previous prime is 29138639. The next prime is 29138651. The reversal of 29138640 is 4683192.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 75889 + ... + 76271.

Almost surely, 2^29138640 is an apocalyptic number.

29138640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 29138640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45425664).

29138640 is an abundant number, since it is smaller than the sum of its proper divisors (61712688).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

29138640 is a wasteful number, since it uses less digits than its factorization.

29138640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 716 (or 710 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 33.

The square root of 29138640 is about 5398.0218599039. The cubic root of 29138640 is about 307.7204975455.

The spelling of 29138640 in words is "twenty-nine million, one hundred thirty-eight thousand, six hundred forty".